Checking for builds being skipped and setting output

action.yml

@@ -18,7 +18,7 @@ inputs:
     required: false
   branch:
     description: "The branch that you would like to deploy to Heroku"
-    default: "HEAD"
+    default: "main"
     required: false
   dontuseforce:
     description: "Set this to true if you don't want to use --force when switching branches"

src/index.ts

@@ -14,6 +14,11 @@ import * as steps from './steps';
     steps.addConfigVars(heroku) &&
     steps.deploy(heroku) &&
     (await steps.performHealthCheck(heroku))
+
+    core.setOutput(
+      "status",
+      "Successfully deployed heroku app from branch " + heroku.branch
+    );
   } catch (error) {
     core.setFailed(error);
   }

src/steps/deploy.ts

@@ -2,7 +2,7 @@
 import * as core from '@actions/core';
 import { execSync } from 'child_process';
 import { IHeroku } from '../types';
-import { ansi_colors } from '../util';
+import { ansi_colors, error_outputs } from '../util';
 
 export const deployDocker = (heroku: IHeroku) => {
   if (heroku.usedocker) {
@@ -39,7 +39,13 @@ export const deployGit = (heroku: IHeroku, shouldThrowError = false) => {
     ? `\`git subtree split --prefix=${heroku.appdir} ${heroku.branch}\``
     : heroku.branch
   try {
-    execSync(`git push ${force} heroku ${finalBranch}:refs/head/main`, { maxBuffer: 104857600 });
+    const output = execSync(`git push ${force} heroku ${finalBranch}:refs/head/main`, { maxBuffer: 104857600 }).toString();
+    if (output.toLowerCase().includes(error_outputs.SKIPPED_WRONG_BRANCH)) {
+      throw new Error(`
+        Unable to deploy code because the deployed branch is not 'main' or 'master' 
+        (Heroku only allows this branch to be deployed)
+      `);
+    }
   } catch (err) {
     if (shouldThrowError) {
       throw err;

src/util.ts

@@ -4,4 +4,8 @@ export const ansi_colors = {
   magenta: '\u001b[35m',
   blue: '\u001b[94m',
   red: '\u001b[91m'
-};
+};
+
+export const error_outputs = {
+  SKIPPED_WRONG_BRANCH: "Pushed to branch other than [main, master], skipping build".toLowerCase()
+}